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2017-11-29crypto: hmac - require that the underlying hash algorithm is unkeyedEric Biggers
Because the HMAC template didn't check that its underlying hash algorithm is unkeyed, trying to use "hmac(hmac(sha3-512-generic))" through AF_ALG or through KEYCTL_DH_COMPUTE resulted in the inner HMAC being used without having been keyed, resulting in sha3_update() being called without sha3_init(), causing a stack buffer overflow. This is a very old bug, but it seems to have only started causing real problems when SHA-3 support was added (requires CONFIG_CRYPTO_SHA3) because the innermost hash's state is ->import()ed from a zeroed buffer, and it just so happens that other hash algorithms are fine with that, but SHA-3 is not. However, there could be arch or hardware-dependent hash algorithms also affected; I couldn't test everything. Fix the bug by introducing a function crypto_shash_alg_has_setkey() which tests whether a shash algorithm is keyed. Then update the HMAC template to require that its underlying hash algorithm is unkeyed. Here is a reproducer: #include <linux/if_alg.h> #include <sys/socket.h> int main() { int algfd; struct sockaddr_alg addr = { .salg_type = "hash", .salg_name = "hmac(hmac(sha3-512-generic))", }; char key[4096] = { 0 }; algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (const struct sockaddr *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key)); } Here was the KASAN report from syzbot: BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:341 [inline] BUG: KASAN: stack-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 Write of size 4096 at addr ffff8801cca07c40 by task syzkaller076574/3044 CPU: 1 PID: 3044 Comm: syzkaller076574 Not tainted 4.14.0-mm1+ #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:341 [inline] sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 crypto_shash_update+0xcb/0x220 crypto/shash.c:109 shash_finup_unaligned+0x2a/0x60 crypto/shash.c:151 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 hmac_finup+0x182/0x330 crypto/hmac.c:152 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 shash_digest_unaligned+0x9e/0xd0 crypto/shash.c:172 crypto_shash_digest+0xc4/0x120 crypto/shash.c:186 hmac_setkey+0x36a/0x690 crypto/hmac.c:66 crypto_shash_setkey+0xad/0x190 crypto/shash.c:64 shash_async_setkey+0x47/0x60 crypto/shash.c:207 crypto_ahash_setkey+0xaf/0x180 crypto/ahash.c:200 hash_setkey+0x40/0x90 crypto/algif_hash.c:446 alg_setkey crypto/af_alg.c:221 [inline] alg_setsockopt+0x2a1/0x350 crypto/af_alg.c:254 SYSC_setsockopt net/socket.c:1851 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1830 entry_SYSCALL_64_fastpath+0x1f/0x96 Reported-by: syzbot <syzkaller@googlegroups.com> Cc: <stable@vger.kernel.org> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-05-23crypto: hmac - add hmac IPAD/OPAD constantCorentin LABBE
Many HMAC users directly use directly 0x36/0x5c values. It's better with crypto to use a name instead of directly some crypto constant. This patch simply add HMAC_IPAD_VALUE/HMAC_OPAD_VALUE defines in a new include file "crypto/hmac.h" and use them in crypto/hmac.c Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-26crypto: include crypto- module prefix in templateKees Cook
This adds the module loading prefix "crypto-" to the template lookup as well. For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly includes the "crypto-" prefix at every level, correctly rejecting "vfat": net-pf-38 algif-hash crypto-vfat(blowfish) crypto-vfat(blowfish)-all crypto-vfat Reported-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-10-14crypto: LLVMLinux: Remove VLAIS usage from crypto/hmac.cJan-Simon Möller
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99 compliant equivalent. This patch allocates the appropriate amount of memory using a char array using the SHASH_DESC_ON_STACK macro. The new code can be compiled with both gcc and clang. Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> Signed-off-by: Behan Webster <behanw@converseincode.com> Reviewed-by: Mark Charlebois <charlebm@gmail.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Cc: pageexec@freemail.hu
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-07-24crypto: hmac - Prehash ipad/opadHerbert Xu
This patch uses crypto_shash_export/crypto_shash_import to prehash ipad/opad to speed up hmac. This is partly based on a similar patch by Steffen Klassert. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-15crypto: hmac - Fix incorrect error value when creating instanceHerbert Xu
If shash_alloc_instance() fails, we return the wrong error value. This patch fixes it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-14crypto: hmac - Switch to shashHerbert Xu
This patch changes hmac to the new shash interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25crypto: hash - Export shash through hashHerbert Xu
This patch allows shash algorithms to be used through the old hash interface. This is a transitional measure so we can convert the underlying algorithms to shash before converting the users across. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10crypto: hash - Fixed digest size checkHerbert Xu
The digest size check on hash algorithms is incorrect. It's perfectly valid for hash algorithms to have a digest length longer than their block size. For example crc32c has a block size of 1 and a digest size of 4. Rather than having it lie about its block size, this patch fixes the checks to do what they really should which is to bound the digest size so that code placing the digest on the stack continue to work. HMAC however still needs to check this as it's only defined for such algorithms. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-05-07[CRYPTO] hmac: Avoid calling virt_to_page on keyHerbert Xu
When HMAC gets a key longer than the block size of the hash, it needs to feed it as input to the hash to reduce it to a fixed length. As it is HMAC converts the key to a scatter and gather list. However, this doesn't work on certain platforms if the key is not allocated via kmalloc. For example, the keys from tcrypt are stored in the rodata section and this causes it to fail with HMAC on x86-64. This patch fixes this by copying the key to memory obtained via kmalloc before hashing it. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-02-07Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)David Howells
Convert instances of ERR_PTR(PTR_ERR(p)) to ERR_CAST(p) using: perl -spi -e 's/ERR_PTR[(]PTR_ERR[(](.*)[)][)]/ERR_CAST(\1)/' `grep -rl 'ERR_PTR[(]*PTR_ERR' fs crypto net security` Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-11[CRYPTO] scatterwalk: Restore custom sg chaining for nowHerbert Xu
Unfortunately the generic chaining hasn't been ported to all architectures yet, and notably not s390. So this patch restores the chainging that we've been using previously which does work everywhere. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] scatterwalk: Use generic scatterlist chainingHerbert Xu
This patch converts the crypto scatterwalk code to use the generic scatterlist chaining rather the version specific to crypto. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-26[CRYPTO]: HMAC needs some more scatterlist fixups.David S. Miller
hmac_setkey(), hmac_init(), and hmac_final() have a singular on-stack scatterlist. Initialit is using sg_init_one() instead of using sg_set_buf(). Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-25[CRYPTO]: Fix hmac_digest from the SG breakage.Vlad Yasevich
Crypto now uses SG helper functions. Fix hmac_digest to use those functions correctly and fix the oops associated with it. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-24SG: Change sg_set_page() to take length and offset argumentJens Axboe
Most drivers need to set length and offset as well, so may as well fold those three lines into one. Add sg_assign_page() for those two locations that only needed to set the page, where the offset/length is set outside of the function context. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-22[SG] Update crypto/ to sg helpersJens Axboe
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-05-02[CRYPTO] templates: Pass type/mask when creating instancesHerbert Xu
This patch passes the type/mask along when constructing instances of templates. This is in preparation for templates that may support multiple types of instances depending on what is requested. For example, the planned software async crypto driver will use this construct. For the moment this allows us to check whether the instance constructed is of the correct type and avoid returning success if the type does not match. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-02-07[CRYPTO] api: Add type-safe spawnsHerbert Xu
This patch allows spawns of specific types (e.g., cipher) to be allocated. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2006-09-23[CRYPTO] hmac: Fix error truncation by unlikely()Herbert Xu
The error return values are truncated by unlikely so we need to save it first. Thanks to Kyle Moffett for spotting this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-23[CRYPTO] hmac: Fix hmac_init update callHerbert Xu
The crypto_hash_update call in hmac_init gave the number 1 instead of the length of the sg list in bytes. This is a missed conversion from the digest => hash change. As tcrypt only tests crypto_hash_digest it didn't catch this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-21[CRYPTO] digest: Remove old HMAC implementationHerbert Xu
This patch removes the old HMAC implementation now that nobody uses it anymore. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-21[CRYPTO] hmac: Add crypto template implementationHerbert Xu
This patch rewrites HMAC as a crypto template. This means that HMAC is no longer a hard-coded part of the API. It's now a template that generates standard digest algorithms like any other. The old HMAC is preserved until all current users are converted. The same structure can be used by other MACs such as AES-XCBC-MAC. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-21[CRYPTO] digest: Added user API for new hash typeHerbert Xu
The existing digest user interface is inadequate for support asynchronous operations. For one it doesn't return a value to indicate success or failure, nor does it take a per-operation descriptor which is essential for the issuing of requests while other requests are still outstanding. This patch is the first in a series of steps to remodel the interface for asynchronous operations. For the ease of transition the new interface will be known as "hash" while the old one will remain as "digest". This patch also changes sg_next to allow chaining. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2005-10-30[PATCH] Use sg_set_buf/sg_init_one where applicableDavid Hardeman
This patch uses sg_set_buf/sg_init_one in some places where it was duplicated. Signed-off-by: David Hardeman <david@2gen.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Greg KH <greg@kroah.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2005-07-06[CRYPTO] Don't check for NULL before kfree()Jesper Juhl
Checking a pointer for NULL before calling kfree() on it is redundant. This patch removes such checks from crypto/ Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!